import numpy as np
arr1 = np.random.randint(1,10,size=(3,3))
print('随机生成的二维整数数组arr1: \n',arr1)
arr2 = np.random.randint(1,10,size=3)
print('随机生成的一维整数数组arr2: \n',arr2)
arr3 = np.random.rand(3,3) * 10
print('随机生成的二维整数数组arr3: \n',arr3)
print('arr1和arr2相加: \n', np.add(arr1,arr2))
print('arr1和arr3相加: \n', np.multiply(arr1,arr3))
print('以 arr1 为底数, arr2 为指数的幂: \n',np.power(arr1, arr2, dtype='int64'))
print('arr1的倒数: \n', np.reciprocal(arr1, dtype='float'))
print('arr3 四舍五入, 小数点后保留一位: \n', np.around(arr3,decimals=1))
print('arr1的余弦值 :\n', np.cos(arr1 * np.pi / 180))